/// <summary>
/// Plots a spiral ring of <see cref="IHexCoordinate" /> with given <paramref name="radius" /> and
/// <paramref name="coordinate" /> as center from inside to outside.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="radius">Radius from <paramref name="coordinate" />. 0 returns <paramref name="coordinate" />.</param>
/// <returns><see cref="IHexCoordinate" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="radius" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> is null.</exception>
public static IEnumerable <IHexCoordinate> Spiral(this IHexCoordinate coordinate, int radius)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (radius < 0)
{
throw new ArgumentOutOfRangeException("radius");
}
if (radius == 0)
{
yield return(coordinate);
yield break;
}
yield return(coordinate);
for (var i = 1; i <= radius; i++)
{
foreach (var current in coordinate.Ring(i))
{
yield return(current);
}
}
}
/// <summary>
/// Plots a ring of <see cref="IHexCoordinate" /> with given <paramref name="radius" /> and
/// <paramref name="coordinate" /> as center.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="radius">Radius from <paramref name="coordinate" />. 0 returns <paramref name="coordinate" />.</param>
/// <returns>A ring of <see cref="IHexCoordinate" />.</returns>
/// <returns>All reachable <see cref="IHexCoordinate" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="radius" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> is null.</exception>
public static IEnumerable <IHexCoordinate> Ring(this IHexCoordinate coordinate, int radius)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (radius < 0)
{
throw new ArgumentOutOfRangeException("radius");
}
if (radius == 0)
{
yield return(coordinate);
yield break;
}
var current = coordinate.Add(HexDirection.E.Distance(radius));
var directions = EnumUtils.Values <HexDirection>().ToList();
foreach (var direction in directions)
{
for (var i = 0; i < radius; i++)
{
yield return(current);
current = current.Neighbor(direction);
}
}
}
/// <summary>
/// Returns all the neighbors of <paramref name="coordinate" />.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <returns>Neighbors of <paramref name="coordinate" /></returns>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> is null.</exception>
public static IEnumerable <IHexCoordinate> AllNeighbors(this IHexCoordinate coordinate)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
return(EnumUtils.Values <HexDirection>().Select(direction => coordinate.Neighbor(direction)));
}
/// <summary>
/// Returns the quotient of two <see cref="IHexCoordinate" />.
/// </summary>
/// <param name="left"><see cref="IHexCoordinate" />.</param>
/// <param name="right"><see cref="IHexCoordinate" />.</param>
/// <returns>Quotient of <paramref name="left" /> and <paramref name="right" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="left" /> is null.</exception>
public static IHexCoordinate Divide(this IHexCoordinate left, int right)
{
if (left == null)
{
throw new ArgumentNullException("left");
}
return(HexCoordinates.Axial(left.Q / right, left.R / right));
}
/// <summary>
/// Field Of View.
/// Returns All visiable <see cref="IHexCoordinate" /> within <paramref name="radius" />.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="radius">Radius from <paramref name="coordinate" />. 0 returns <paramref name="coordinate" />.</param>
/// <param name="isOpaque">Returns if <see cref="IHexCoordinate" /> is opaque.</param>
/// <returns>All visiable <see cref="IHexCoordinate" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="radius" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> or <paramref name="isOpaque" /> is null.</exception>
public static IEnumerable <IHexCoordinate> FieldOfView(this IHexCoordinate coordinate, int radius,
Func <IHexCoordinate, bool> isOpaque)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (isOpaque == null)
{
throw new ArgumentNullException("isOpaque");
}
if (radius < 0)
{
throw new ArgumentOutOfRangeException();
}
if (isOpaque(coordinate))
{
yield break;
}
yield return(coordinate);
if (radius == 0)
{
yield break;
}
var shadowCast = new ShadowCast();
for (var ringIndex = 1; ringIndex <= radius; ringIndex++)
{
var isEven = ringIndex % 2 == 0;
var slide = (double)360 / (6 * ringIndex);
for (var hexIndex = 0; hexIndex < ringIndex * 6; hexIndex++)
{
var ring = new RingHexCoordinate(coordinate, ringIndex, hexIndex);
var current = ring.ConvertTo();
var minAngle = hexIndex * slide;
if (isEven)
{
minAngle -= slide / 2;
}
var maxAngle = minAngle + slide;
var center = (maxAngle + minAngle) / 2.0;
// Ignore if the center of the hex cannot be seen
if (shadowCast.Hide(center))
{
continue;
}
yield return(current);
// Add to shadow if the hex is opaque
if (isOpaque(current))
{
shadowCast.AddShadow(minAngle, maxAngle);
}
}
}
}
/// <summary>
/// Use this as a center to rotate other <see cref="HexCoordinate" />.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="target"><see cref="IHexCoordinate" /> to be rotated.</param>
/// <param name="times">Number of 60°. Positive for clockwise.</param>
/// <returns>Rotated <see cref="IHexCoordinate" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="times" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> or <paramref name="target" /> is null.</exception>
public static IHexCoordinate Rotate(this IHexCoordinate coordinate, IHexCoordinate target, int times)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (target == null)
{
throw new ArgumentNullException("target");
}
if (times < 0)
{
throw new ArgumentOutOfRangeException("times");
}
times %= 6;
if (times == 0)
{
return(target);
}
var vectorPx = target.X - coordinate.X;
var vectorPy = target.Y - coordinate.Y;
var vectorPz = target.Z - coordinate.Z;
var isOdd = times % 2 == 1;
times %= 3;
var isPositive = times > 0;
times = Math.Abs(times);
for (var i = 0; i < times; i++)
{
int temp;
if (isPositive)
{
temp = vectorPx;
vectorPx = vectorPz;
vectorPz = vectorPy;
vectorPy = temp;
}
else
{
temp = vectorPx;
vectorPx = vectorPy;
vectorPy = vectorPz;
vectorPz = temp;
}
}
if (!isOdd)
{
return(HexCoordinates.Cube(vectorPx + coordinate.X, vectorPy + coordinate.Y, vectorPz + coordinate.Z));
}
vectorPx = -vectorPx;
vectorPy = -vectorPy;
vectorPz = -vectorPz;
return(HexCoordinates.Cube(vectorPx + coordinate.X, vectorPy + coordinate.Y, vectorPz + coordinate.Z));
}
/// <summary>
/// <para>
/// Plots a approximate line between <paramref name="start" /> and <paramref name="destination" />.
/// </para>
/// </summary>
/// <param name="start">Start <see cref="IHexCoordinate" />.</param>
/// <param name="destination">Destination <see cref="IHexCoordinate" />.</param>
/// <returns>All <see cref="IHexCoordinate" /> pass through <paramref name="start" /> and <paramref name="destination" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="start" /> or <paramref name="destination" /> is null.</exception>
public static IEnumerable <IHexCoordinate> Line(this IHexCoordinate start, IHexCoordinate destination)
{
var distance = start.Distance(destination);
for (var i = 0; i <= distance; i++)
{
yield return(Round(LinearInterpolation(start.X, destination.X, distance, i),
LinearInterpolation(start.Y, destination.Y, distance, i),
LinearInterpolation(start.Z, destination.Z, distance, i)));
}
}
/// <summary>
/// <para>
/// Converts <paramref name="target" /> to a relative <see cref="IRingCoordinate" /> with respect to
/// <paramref name="coordinate" />.
/// </para>
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="target"><see cref="IHexCoordinate" /> to be converted.</param>
/// <returns><see cref="IRingCoordinate" /> with respect to <paramref name="coordinate" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> or <paramref name="target" /> is null.</exception>
public static IRingCoordinate ToRing(this IHexCoordinate coordinate, IHexCoordinate target)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (target == null)
{
throw new ArgumentNullException("target");
}
var different = target.Subtract(coordinate);
var xOffset = Math.Abs(different.X);
var yOffset = Math.Abs(different.Y);
var zOffset = Math.Abs(different.Z);
int directionIndex;
if (yOffset >= xOffset)
{
if (zOffset >= yOffset)
{
directionIndex = different.Z > 0 ? 3 : 0;
}
else
{
directionIndex = different.Y > 0 ? 5 : 2;
}
}
else if (xOffset >= zOffset)
{
directionIndex = different.X > 0 ? 1 : 4;
}
else
{
directionIndex = different.Z > 0 ? 3 : 0;
}
var radius = (xOffset + yOffset + zOffset) / 2;
// Direction start from E
var direction = EnumUtils.Values <HexDirection>().Shift(-2).ToList();
// Find the counter-clockwise corner tile.
var corner = coordinate.Add(direction[directionIndex].Distance(radius));
different = target.Subtract(corner);
xOffset = Math.Abs(different.X);
yOffset = Math.Abs(different.Y);
zOffset = Math.Abs(different.Z);
var excess = (xOffset + yOffset + zOffset) / 2;
// Our tile is at the corner's index, plus this excess.
var index = radius * directionIndex + excess;
var ringSize = 6 * radius;
index = (index + ringSize - (radius + 1) / 2) % ringSize;
return(HexCoordinates.Ring(coordinate, radius, index));
}
/// <summary>
/// Returns the difference of two <see cref="IHexCoordinate" />.
/// </summary>
/// <param name="left"><see cref="IHexCoordinate" />.</param>
/// <param name="right"><see cref="IHexCoordinate" />.</param>
/// <returns>Difference of <paramref name="left" /> and <paramref name="right" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="left" /> or <paramref name="right" /> is null.</exception>
public static IHexCoordinate Subtract(this IHexCoordinate left, IHexCoordinate right)
{
if (left == null)
{
throw new ArgumentNullException("left");
}
if (right == null)
{
throw new ArgumentNullException("right");
}
return(HexCoordinates.Axial(left.Q - right.Q, left.R - right.R));
}
/// <summary>
/// Returns true if there is nothing blocking between <paramref name="coordinate" /> and <paramref name="target" />.
/// Do not use this to find the field of view.
/// Uses <see cref="FieldOfView" /> to have better performance.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="target"><see cref="IHexCoordinate" /> to be checked.</param>
/// <param name="isOpaque">Returns if <see cref="IHexCoordinate" /> is opaque.</param>
/// <returns>True if there is nothing blocking between <paramref name="coordinate" /> and <paramref name="target" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> or <paramref name="isOpaque" /> is null.</exception>
public static bool Visible(this IHexCoordinate coordinate, IHexCoordinate target,
Func <IHexCoordinate, bool> isOpaque)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (isOpaque == null)
{
throw new ArgumentNullException("isOpaque");
}
return(!coordinate.Line(target).Any(isOpaque));
}
/// <summary>
/// <para>
/// Initializes a new <see cref="IHexCoordinate" /> from current position with given <paramref name="direction" />
/// and <paramref name="distance" />.
/// Diagonal of <see cref="HexDirection.A" /> is the other neighbor of <see cref="HexDirection.A" /> and
/// <see cref="HexDirection.B" />.
/// </para>
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="direction">Direction of the new <see cref="IHexCoordinate" /> from <paramref name="coordinate" />.</param>
/// <param name="distance">Distance from <paramref name="coordinate" />. 0 returns <paramref name="coordinate" />.</param>
/// <returns>Requested <see cref="IHexCoordinate" /></returns>
/// <exception cref="ArgumentOutOfRangeException">
/// <para><paramref name="distance" /> < 0.</para>
/// <para><paramref name="direction" /> out of range.</para>
/// </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> is null.</exception>
public static IHexCoordinate Diagonal(this IHexCoordinate coordinate, HexDirection direction, int distance = 1)
{
if (distance == 0)
{
return(coordinate);
}
if (distance < 0)
{
throw new ArgumentOutOfRangeException("distance");
}
int qOffset;
int rOffset;
switch (direction)
{
case HexDirection.A:
qOffset = 1;
rOffset = 1;
break;
case HexDirection.B:
qOffset = -1;
rOffset = 2;
break;
case HexDirection.C:
qOffset = -2;
rOffset = 1;
break;
case HexDirection.D:
qOffset = -1;
rOffset = -1;
break;
case HexDirection.E:
qOffset = 1;
rOffset = -2;
break;
case HexDirection.F:
qOffset = 2;
rOffset = -1;
break;
default:
throw new ArgumentOutOfRangeException("direction");
}
return(coordinate.OffsetDistance(qOffset, rOffset, distance));
}
/// <summary>
/// <para>
/// Calculates distance between two <see cref="IHexCoordinate" />, <paramref name="start" /> and
/// <paramref name="destination" />.
/// </para>
/// </summary>
/// <param name="start">Start <see cref="IHexCoordinate" />.</param>
/// <param name="destination">Destination <see cref="IHexCoordinate" />.</param>
/// <returns>Distance between <paramref name="start" /> and <paramref name="destination" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="start" /> or <paramref name="destination" /> is null.</exception>
public static int Distance(this IHexCoordinate start, IHexCoordinate destination)
{
if (start == null)
{
throw new ArgumentNullException("start");
}
if (destination == null)
{
throw new ArgumentNullException("destination");
}
return((Math.Abs(start.X - destination.X) +
Math.Abs(start.Y - destination.Y) +
Math.Abs(start.Z - destination.Z)) / 2);
}
/// <summary>
/// Returns all the <see cref="IHexCoordinate" /> that can be reached by given <paramref name="steps" /> from
/// <paramref name="coordinate" />.
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="steps">Maximum steps can be used. 0 returns itself.</param>
/// <param name="isOpaque">Returns if <see cref="IHexCoordinate" /> is opaque.</param>
/// <returns>All reachable <see cref="IHexCoordinate" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="steps" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> or <paramref name="isOpaque" /> is null.</exception>
public static IEnumerable <IHexCoordinate> Reachable(this IHexCoordinate coordinate, int steps,
Func <IHexCoordinate, bool> isOpaque)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (isOpaque == null)
{
throw new ArgumentNullException("isOpaque");
}
if (steps < 0)
{
throw new ArgumentOutOfRangeException("steps");
}
if (steps == 0)
{
yield return(coordinate);
yield break;
}
var visited = new HashSet <IHexCoordinate> {
coordinate
};
var fringes = new List <IHexCoordinate> {
coordinate
};
for (var i = 1; i <= steps; i++)
{
var newFringes = new List <IHexCoordinate>();
foreach (var currentCoordinate in fringes)
{
foreach (var direction in EnumUtils.Values <HexDirection>())
{
var neighbor = currentCoordinate.Neighbor(direction);
if (visited.Contains(neighbor) || isOpaque(neighbor))
{
continue;
}
visited.Add(neighbor);
newFringes.Add(neighbor);
yield return(neighbor);
}
}
fringes = newFringes;
}
}
public RingHexCoordinate(IHexCoordinate center, int radius, int index)
{
if (center == null)
{
throw new ArgumentNullException("center");
}
if (radius < 0)
{
throw new ArgumentOutOfRangeException("radius");
}
if (index < 0)
{
throw new ArgumentOutOfRangeException("index");
}
_radius = radius;
_index = index;
_center = center;
}
/// <summary>
/// <para>
/// Returns all <see cref="IHexCoordinate" /> within <paramref name="radius" /> and <paramref name="coordinate" />
/// as center.
/// </para>
/// </summary>
/// <param name="coordinate">Current <see cref="IHexCoordinate" />.</param>
/// <param name="radius">Radius from <paramref name="coordinate" />. 0 returns <paramref name="coordinate" />.</param>
/// <returns>All <see cref="IHexCoordinate" /> within <paramref name="radius" />.</returns>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="radius" /> < 0. </exception>
/// <exception cref="ArgumentNullException"><paramref name="coordinate" /> is null.</exception>
public static IEnumerable <IHexCoordinate> Range(this IHexCoordinate coordinate, int radius)
{
if (coordinate == null)
{
throw new ArgumentNullException("coordinate");
}
if (radius == 0)
{
yield return(coordinate);
yield break;
}
if (radius < 0)
{
throw new ArgumentOutOfRangeException("radius");
}
for (var dx = -radius; dx <= radius; dx++)
{
for (var dy = Math.Max(-radius, -dx - radius); dy <= Math.Min(radius, -dx + radius); dy++)
{
yield return(HexCoordinates.Cube(dx, dy, -dx - dy).Add(coordinate));
}
}
}
public bool TryGetValue(IHexCoordinate coordinate, out T value)
{
return(_grid.TryGetValue(coordinate, out value));
}
public void Add(IHexCoordinate coordinate, T value)
{
_grid.Add(coordinate, value);
}
public T this[IHexCoordinate coordinate]
{
get { return(_grid[coordinate]); }
set { _grid[coordinate] = value; }
}
int IGraph <IHexCoordinate> .OutDegree(IHexCoordinate node)
{
return(node.AllNeighbors().Count(n => _grid.ContainsKey(n)));
}
/// <summary>
/// <para>
/// Initializes a new instance of <see cref="IRingHexCoordinate" />.
/// </para>
/// </summary>
/// <param name="center">Center of <see cref="IRingHexCoordinate" />.</param>
/// <param name="radius">Radius from <paramref name="center" />.</param>
/// <param name="index">
/// Index start from 0. Count from the top of <paramref name="center" />.
/// If there are two, take the one on right.
/// </param>
/// <returns>New <see cref="IRingHexCoordinate" />.</returns>
/// <exception cref="ArgumentNullException"><paramref name="center" /> is null</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="radius" /> or <paramref name="index" /> < 0</exception>
public static IRingHexCoordinate Ring(IHexCoordinate center, int radius, int index)
{
return(new RingHexCoordinate(center, radius, index));
}
public bool Equals(IHexCoordinate obj)
{
return(Equals(ConvertTo(), obj));
}
public Region(IHexCoordinate center, int radius)
{
Center = center;
Radius = radius;
}
public bool Equals(IHexCoordinate obj)
{
return(obj.Q == Q && obj.R == R);
}
public bool ContainsKey(IHexCoordinate coordinate)
{
return(_grid.ContainsKey(coordinate));
}
IEnumerable <IHexCoordinate> IGraph <IHexCoordinate> .Neighbors(IHexCoordinate node)
{
return(node.AllNeighbors().Where(n => _grid.ContainsKey(n)));
}
public void Initialize()
{
Center = HexCoordinates.Cube(1, 1, -2);
}
